Variable capacity compressor



June 5, 1928 1,671,984

W. GOODMAN VARIABLE CAPACITY COMPRESSOR- Filed Nov. 18, 1926 4 Sheets-Sheet l ILLIAM GOODMAN l OR ATTORNEY June 5, 1928.

w. GOODMAN VARIABLE CAPACITY COMPRESSOR Filed Nov. 18, 1926 4 Sheets-Sheet 2 [H 1 M L4 J1 fll /-e LO\ 6 I -,& T

i V WILLIAM GooDMAN.

ATTORNEY June 5, 1928.

W. GQODMAN VARIABLE CAPACITY COMPEESSOR 4 Sheets-Sheet Filed Nov. 18, 1926 TOP WILLIAM GOODMAN.

HATTORNEY June 5, 1928. 1,671,984

w. GOODMAN VARIABLE CAPACITY COMPRESSOR Filed Nov. 18, 1926 I 4 Sheets-Sheet 4 DISKLHAR SUCTION I NTA SUCTION DISCHARGE ATTORNEY ILLIAM Gooomm I ENTOR Patented June 5, 1928.

' UNITED STATES PATENT} OFFICE.

WILLIAM GOODMAN, OI ENGLEWOOD, NEW JERSEY, ASBIGNOB TO WOBTH ING'ION PUMP AND MACHINERY CORIORATION, OF NEW YORK, N. Y., A COBYOBA'I'ION OI VIRGINIA.

VARIABLE CAPACITY COMPRESSOR.

Application filed November 18, 1926. Serial No. 149,088.

This invention relates to air or gas compressors and more particularly to a multiple stage, compressor.

An object of the invention is to rovide a compressor particularly applicable or Diesel engine injection service in which certain of the cylinders may be alternativel connected in series for variation of the e ective displacement of the compressor.

Another object of the invention is to provide a compressor embodying various advantages such as the case of control of the compressor for varying the effective displacement ofthe compressor, the complete absence of clearance pockets, simplicity of construction, andthe possible wide range of pressure output of the compressor together with its eflicient operation.

The invention comprises a multiple cylinder or 'multi-stage compressor in which a pre-determined number of cylinders operate actively at one time, while at other times certain other of the cylinders are brought into active operation, while .certain of the cylinders are idle, whereby a pre-determined lower pressure for the same amount of air used; the same or a pre-determined desired pressure maintained in the line upon the use of a lesseramount of air therefrom; or both the pressure and quantity of air, under pressure, available for use may be reduced, said cylinders being connected to operate in series. With these objects in view, the invention consists in'various features of construction and combination of parts, which will be first described in connection with the accompanying drawings, showing a com ressor of the preferred form' embodying t e invention, and the features forming t e be specifically pointed out in the claims.

Flgure 1 is a side elevation of the improved compressor showing it associated with the inter and after coolers and companion mechanisms.

Figure 2 is a longitudinal section through the compressor.

Figure 3 is a cross section through the compressor taken on 'the line 3-3 of Figure 2. 3

Figure 4 is a fragmentary view artly in section showing; the by-pass of t compressor and Fi re 5's a cross section on the line M of Figure 2.

invention will Figure 6 is a detailed section of the valve block and valve em loyed for automatically cutting out'one of t e cylinders of the compressor.

Figure 7 is a view of a modified form of the compressor.

Referring more particularly to the drawings, the improved compressor illustrated in the drawings is in effect a four cylinder or four-stage compressor, three sta of which operate actively at one time. he compressor includes the main housing A which contains the cylinders 1, 2, 3 and 4 of the first, second, third and fourth stages respectively of the compressor.

When high outlet pressure is desired the air or gas to be compressed enters the cylinder 1 through the suction valves 5 and 6,

which may be of any approved construction and are hand operated for unseating through the medium of the hand wheels7. The air compressed within the cylinder 1 by the iston 8 leaves the c linder throu h the ischarge valves 9 an 10 entering t e passagethe intercooler 13 the compressed fluid passes through the pipe or connection 14 and enters the cylinder2 throu h the suction or intake valve 15. The flui is further compressed within. the cylinder 2 by the piston 16 and discharges. jrom the cylinder throu h the outlet or discharge valve 17 assin t rough the connection 18 into and t on i the second stage intercooler from -.whic it passes through the suction valve 20 of the third stage into the c linder 3 where it is further compressed by t 0 piston 21. From the discharge or outlet valve 22 of the third stage of compression of cylinder 3 the compressed fluid passes into the cooler 23 which serves as the third stage intercooler and as the after cooler of the compressor installation. When maximum quaint and pressure of compressed air is desired the first, second and third stages of the compressor operate to compress the air to the desired pressure, for

instance, to 1000 pound pressure and thus I 25' is held seated to close the ports 25 by body 24 has a check valve 25. ositioned therein which. controls the flow o the fluid under pressure either through the pipe 27 to the suction 28 of the fourth -or last stage of the compressor or through the pipe 29 to the bottle 30 or to the discharge line from which the fluid is used.

It is to'he understood that any suitable type of check valve may be employed in lieu of the particular type illustrated in Fig. 6

of the drawings. In the check valve structure 25 shown in Fig. 6, the valve member the spring 25". When the valve 25 is seated the air will pass out through the pipe 27.

, When however, the pressure of air or fluid ,exceeds a predetermined pressure, it will raise the valve 25 against the tension of the spring 25 and open the ports 25 to permit the air to pass through the pipe 29 direct tothe bottle or reservoir 30. I

1When the compressor is delivering high .pressure air, that is, when the first," second necting parts are under the high pressure,

such as'900 pounds. Part of the air or fluid discharged third stage of the compressor passes through thecheck valve 25 to the bottle 30 or discharge line, the pressure being great enough to unseat the check valve, and allows the.

third stage todischarge directto the-bottle or discharge, line through the cooler 23. However, at this time part of the high pressure air or fluid will pass through the pipe 27'in'to the'fourth stage of the compressor,

.' passing into the cylinder 4 under the high pressure, from which cylinder it is discharged at the same pressure at which it enters, so that this final or fourth cylinder does no work under this condition but is drawing in fluid and discharging it at the same pressure, or. in other words, the last or fourth stage of the compressor will idle.

'Wlien it is desired to have a lower maximum output pressure of fluid the valve 31 is opened manually by means of the hand wheel 32 which connects the discharge of the, cylinder 1 with the suction side of the cylinder which permits air or gas to be taken into the suction of the cylinder 2 directly from the intake of the compressor. When the'valve 31 is opened the air or gas passes from the intake chamber 33 through the "valve structure 31 into the by-pass 34:, which at this high pressure by the,

by-pass extends downwardly through the housing A as shown at 35 on Figures 3 and 4 of the drawing into the suction of the cylinder 2. When the valve 31 is closed and the compressor is operating with the fourth stage idling, the fluid from the discharge side of the, first stage passes through the passageway'35 to the suction of the second stage; however, the opening of the valve 31 forms a by-pass about the cylinder 1 and permits the fluid to be compressed to pass directly tothe suction of the cylinder '2. In order'to avoid any work done by the first stage or cylinder 1, at this time the suction valves 5 and 6 are lifted, from their pockets,

'-manually by means of the hand wheels 7 which permits free air passage through the first stage or cylinder 1. When the air or other fluid is by-pa-ssing about the-cylinder 1 to the cylinder 2 and no air is being de-' livered by the first stage, the piston 16 is then acting with its cylinder 2 as the first stage ofthe compressor.

Under this condition the pipes 29, 4:1 and 39 are under the a high-pressure, for instance, 900 pounds, or

the pressure against which the final or fourth stage of the compressor is working,

and the pressure existing in the bottle 30 or discharge line. The pipe 27 and the tubes of the intercooler 23 connected with the said pipe are under the pressure against which the piston 21 of the third stage of the compressor is operating, which is considerably lower than the high pressure against which the final stage of the compressor is working,

for example, 300 pounds; therefore, the pressure on the top of the check valve 25 is,

for-example, 900 pounds, and the pressure 1 on the bottom or under,the valve is, for example 300 pounds, hence, the valve 25 remains closedand cuts off communication between. the cylinder 3 and the bottle 30 through the pipe .29, and causes all of the the fourth or final stage of the compressor.

While in the foregoing description and in the drawings, a four-stage compressor has been described and illustrated, it is to be air or fluid being compressed to pass into understood that the present invention is applicable to multi-stage compressors having any number of stages and that while in the foregoing description only one of the stages of the compressor idles or is inactive from a compressing standpoint at one time, it is to be understood that a plurality of the stages may idle sucharrangement being possible by a mere uplication of the by-pass construcgion comprising the valve 31 and passageway In Figure 7 of the drawings a modified form of the invention is diagrammatically shown in which a by-pass 50 is provided between the suction of the second .stage 52 of the compressor and the suction of the third stage 53 of t-liz: :OIllPlGSSOI, the said by-pass being controlled by a manually operable valve 54 to permit the by-passing of the air from the suction of the second stage 52 of the compressor to the suction of the third stage 53 so'as to render the second stage 52 of the compressor inactive from a compressing standpoint. This construction also shows the by-pass 55 between the suction of the first stage 51 of the compressor and the suction of the second stage 52, the said bypass being controlled by a manually operated valve 56 so as to permit the cutting out of the first stage 51 of the compressor as well as the second stage 52. It will be seen that without this construction either the first stage 51 or the second stage 52 or both of these stages may be cut out or rendered inactive from a compressing standpoint. While only two of the cylinders are shown with the bypasses, it is to be understood that any number of them may be so constructedwithoutdepartingfrom the spirit of this invention.

Generically, the operation of the'improved compressor is as follows: The compressor is designed to supply air orgas under a low maximum. output pressure, to supply a1r or gas under a high maximum output pressure, to provide lower pressure of air for the same amount of air used, to provide the same pressure for a less amount or quantity of air used and to reduce both pressure and amount of air available for use. When the lesser quantity of air under the maximum pressure is desired or both the pressure and amount available for use are to be reduced,

the first stage of the compressor is cut out I by opening the valve 31 which connects the discharge side of the first stage or cylinder 1 to the suction side and opens up connection between the suction side of the cylinder 1 with the suction sidetof the cylinder 2 or second stage of the compressor, so that the .fluid to be compressed is taken directly from the. source of supply to the suction of the second stage. The performance of any work by the first stage of the compressor, at this.

time, is prevented by lifting the suction valves 5 and 6 including their casing from the other pockets by means of the hand wheels 7 which permits free air passage through the cylinder-.1.

With the first stage of the compressor cut out the air passes from the third stage or cylinder 3 into the fourth stage or cylinder 7 4, which means that three stages of the fourstage compressor, in all, are in (meration and that these stages are connected in series through the intercoolers.

Closing all three of the valves, 5, 6 and 31 brlng the first stage of the compressor into active operation and with the first stage operating the fourth stage or' cylinder 4 becomestoo small to handle all the air and most of it passes by the opening of check valve 25 directly from the third stage or cylityof cylinders connect .stage compression'is used with the stages or cylinders connected in series and it will also be apparent that the same combination or arrangement can be worked out for three stages, having a combination of two stages operating in series for different pressures or for any desired number of stages without departing from the s irit of this invention.

By partially opening the valve 31 the quantity of the air compressed may be regulated to any desired amount'in that such opening will permit passage of some of the air about the first stage of the compressor direct to the second stage ofthe compressor and entering the suction of the second stage without having passed through the first stage, it will retard the volume of air delivered by the first stage to the second stage owing to the fixed capacity of the second stage, and by regulating the size of the communicating opening between the suction chamber 33 of the first stage and the by-pass 34, by regulating the movement of the valve 31, the amount-ofair by-passed-to the suction of the second stage may be regulated.

a It will be understood that the invention is not to be limited to the specific construction vention defined by the claims.

Whatis claimed is:

1. In a multi-stage compressor, a plural ity of cylinders connected in series and means controlled by pressure of fluid compressed for preventing at pie-determined times thepassage of the ma or quantit of the fluid compressed to the last stage 0 the compressor atwhich time said last stage will be non-compressing.

2. In a multi-stage compressor, a plurality of compressing cylinders connected in series, means for by-passing the fluid to be compressed about one of the cylinders and direct to the suction of the succeeding stage cylinder to lower the efiective displacement of the compressor, and means for unseating the suction valves of said first named cylinder to render it non-compressing.

3. In a multi-stage compressor, a plurality of cylinders connected in series and having their discharge to the suction of the cylinder next in succession, a valve for opening communication from the suction of one of said cylinders to the suction of the next of the cylinder for lowering the efiective disluo .cylinder in succession to permit cutting out placement of the compressor, and means for unseating the suction valve of the cylinder means disposed in the connection between the two last stage cylinders and controlled by pressure of fluid compressed to direct fluid compressed at prc-determined times to the discharge line from the next to the last stage cylinder whereby the last stage cylinder will idle.

5. In a multi-stage compressor, a plurality of cylinders connected in series, means disposed in the connection between later stage cylinders to direct fluid compressed above a pre-determined pressure direct to the discharge line from a stage cylinder before the last stage whereby the last stage cylinder will idle, and means for rendering an'earl stage cylinder inactive for lowering the e fective displacement of the compressor.

6. In a multi-stage compressor, a plurality of cylinders connected in series, means disposed in the connection between the two last stage cylinder-s to direct fluid compressed above a pie-determined pressure direct to the discharge line from the next to the last stage cylinder whereby the last stage cylinder will idle, and means for Icy-passing the fluid to be compressed about one of the cylinders and direct to the suction of the succeeding stage cylinder forlowering the eflective displacement of the compressor.

7. In a multi-stage compressor, a plurality of cylinders connected in series, a passage-' way from the intake of one of said cylinders to the intake of another of the cylinders,

a a valve for opening up said (passageway to permit fluid to be compresse to flow from the intake ofsaid-first mentionedcylinder direct to said other cylinder, and means to render the first mentioned cylinder noncompress'ing when said valve is open.

8. In a multi-stage compressor, a plurality of cylinders connected in series, a valve for opening communication from the suction of one of said cylinders to the suction of a cylinder in the series to permit cylinder cutting out for lowering the eflective displacement-of thecompressor, and means for unseating the suction valve of the cylinder cutout to render it non-compressing.

9. In a multi-stage compressor, a plurality of compressing cylinders connected in series, means tain of said cylinders in series IOI' varying for alternatively connecting oerthe effective displacement of the compressor,

and pressure controlled means for rendering the last stage non-compressing at predetermined times. 7

10. In a multi-stage compressor, a plurality of compressing cylinders, means for by passing the fluid to be compressed direct to the suction of a later stage cylinder to lower the effected displacement of the compressor, and pres-sure controlled means for rendering the last stage non-compressing at predetermined times.

In testimony whereof I aflix mysignature.

WILLIAM, GOODMAN. 

